Echinococcosis, also known as hydatid disease, is a parasitic infection caused by tapeworm larvae belonging to the genus Echinococcus. The two main species responsible for human infections are Echinococcus granulosus and Echinococcus multilocularis. This disease is prevalent in many parts of the world, especially rural areas where livestock farming and dog ownership are common.
Historical Context and Discovery: Echinococcosis has been known to humans for centuries. The first documented case of hydatid cysts in humans was reported in ancient Egypt around 1500 BCE. However, the connection between hydatid cysts and dog tapeworms (the adult form of the Echinococcus parasite) was not established until the late 18th century. The complete life cycle of Echinococcus and its transmission between different hosts were discovered in the late 19th and early 20th centuries.
Prevalence: Echinococcosis is considered a neglected tropical disease and is endemic in many parts of the world, particularly in rural and remote regions. The global prevalence is estimated to be around 2-3 million cases, with 200,000 new cases occurring annually. However, due to underreporting and limited surveillance, the actual number of cases could be much higher.
Transmission Routes: The primary mode of transmission is through the ingestion of parasite eggs shed in the feces of infected dogs or other canids. These eggs contaminate the environment, particularly soil, water, and vegetation. Humans become infected by accidentally ingesting the eggs, usually through consuming contaminated food or water. Ingested eggs release larvae that penetrate the intestinal wall and migrate to various organs, mainly the liver and lungs, where they form cysts.
Affected Populations: Echinococcosis can affect both humans and animals. Certain populations are at higher risk due to specific activities and lifestyle factors. These include livestock farmers and shepherds who have direct contact with infected animals, rural populations in resource-poor settings with limited access to healthcare and sanitation, indigenous communities heavily reliant on subsistence farming or hunting, dog owners or those living in close proximity to infected dogs, and individuals with immunodeficiency or weakened immune systems.
Key Statistics: Echinococcosis is responsible for significant morbidity and mortality worldwide, causing an estimated 50,000 deaths annually with a global disability-adjusted life year (DALY) burden of around 1.2 million. The majority of deaths occur due to complications from cyst rupture, leading to anaphylactic shock or secondary infections.
Risk Factors: Several factors influence the transmission of Echinococcosis, including the presence of infected definitive hosts (dogs, foxes, and coyotes) in the community, poor sanitation and hygiene practices, lack of knowledge about the disease and preventive measures, presence of infected intermediate hosts (livestock, rodents, small mammals) in the environment, and human-animal interactions, particularly close contact with infected animals or handling their feces.
Impact on Regions and Populations: The prevalence of echinococcosis varies across different regions. It is more common in areas where traditional livestock farming is practiced, such as Central Asia, parts of southern Europe, South America, and parts of China. Prevalence can range from 5% to 10% in certain communities in these regions. In contrast, the disease is relatively rare in developed countries with efficient control programs and improved healthcare infrastructure.
Echinococcosis can have a significant economic impact in affected regions. The disease affects livestock productivity and can lead to significant economic losses in the agricultural sector. It also has a profound impact on affected individuals and their families due to the high cost of diagnosis, treatment, and potential surgical interventions.
In conclusion, Echinococcosis is a global health concern, particularly in rural and resource-limited settings. Understanding its epidemiology, transmission routes, affected populations, and risk factors is crucial for the development of effective prevention and control measures to reduce the burden of this parasitic infection.

Download Data(下载数据)

Seasonal Patterns: Analysis of data on cases of Echinococcosis in mainland China reveals a clear seasonal pattern in the occurrence of this disease. The number of cases demonstrates fluctuations throughout the year, with certain months exhibiting a higher incidence compared to others.
Peak and Trough Periods: The peak periods for Echinococcosis cases in mainland China occur during December, January, and February, with a significant increase in the number of cases observed. On the contrary, the trough periods, characterized by the lowest number of cases, coincide with May, June, and July.
Overall Trends: An examination of the overall data reveals a rise in the number of Echinococcosis cases in mainland China over the span of 2010 to 2023. Despite fluctuations in certain years, an upward trend prevails. However, it is important to note that negative values for the number of cases are recorded in some months, particularly in early 2013 and early 2023. These negative values may be attributed to data reporting errors or other factors that affect data accuracy.
Discussion: The observed seasonal pattern of Echinococcosis cases in mainland China is likely influenced by various factors. Environmental conditions, such as temperature and humidity, may play a role in the life cycle of the parasite and its transmission to humans. Additionally, human behaviors and activities, including agricultural practices or contact with infected animals, could contribute to the seasonal variation.
The peak periods in December, January, and February may be attributed to factors such as increased contact with livestock or seasonal changes in human behavior that elevate the risk of transmission. Conversely, the trough periods in May, June, and July could be influenced by factors such as reduced contact with livestock or alterations in environmental conditions that decrease the risk of transmission.
The overall upward trend in the number of cases indicates that Echinococcosis remains a public health concern in mainland China. Further investigation and understanding of the specific factors contributing to disease transmission, as well as the development and implementation of effective prevention and control measures, are necessary to alleviate the burden of Echinococcosis on the population.